Stabilized four legged table



Sept. 7, 19 65 R. HENDERSON 3,204,906

STABILIZED FOUR LEGGED TABLE Filed April 16, 1964 35 26 [2 3(2 5% 5'2 [0\ jg 52 54 32 m AZ? lgfi. Ag- L will 726 T I '1 Th LLM. ulu I k lu 3 Z i 5?) g I i 5 3 I 54, /6/ 26 26 i212 34 Z i" 53 5 a. y I

INVENTOR.

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United States Patent 3,204,906 STABILIZED FOUR LEGGED TABLE Robert Henderson, 40 Mohawk Road, Short Hills, NJ. Filed Apr. 16, 1964, Ser. No. 360,396

8 Claims. (Ci. 243-1883) This invention relates to a four legged table which may be readily stabilized when resting upon an uneven floor surface.

It is well known that tables having three legs rest in a stable condition upon a floor surface even though that surface is uneven; but that if tables which are, most commonly, rectangular or circular in shape are provided with only three triangularly arranged legs, the table objectionably tends to tip if much weight is imposed thereupon outside of the triangle. Because of that tipping tendency, tables are generally provided with four rectangularly arranged legs.

Such four legged tables, however, suffer the drawback that, while they are so manufactured that they rest in a stable condition upon a plane or perfectly even floor surface, they wobble objectionably when the floor upon which they are placed is not prefectly even, as is often the case.

Efforts hitherto put forth toward stabilizing four legged tables have had such unsatisfactory results that a common practice now pursued to steady or stabilize a four legged table is merely to put a makeshift wedge under the one of the legs which is short of contact with the floor. As

a proper wedge is seldom available, a match book or a folded piece of paper generally is used for the purpose; something awkward to do and often failing to accomplish the desired purpose.

An important object of this invention is the provision of a four legged table which stabilizes itself when placed upon an uneven floor surface.

Another important object is the provision of such a table which stabilizes itself automatically and includes holding means for holding it in stabilized condition.

Another important object is the provision of such a table in which the mentioned holding means operate automatically.

Another important object is the provision of such a table which, when stabilized, is not subject to the mentioned tipping tendency of a three legged table.

The foregoing and other more or less obvious objects are accomplished according to this invention by suitably making two similar legs at one side of the table rigid with the table top as is customary practice and by rigidly unifying the other two legs, at their upper ends, by a rigid crossbar which, with the two legs, forms an inverted U. The ends of the U are the feet of the unified legs, and this unified leg assembly is pivotably connected, at the center of the crossbar, to the side of the table which is opposite to the first-mentioned rigid legs at a point equidistant from said first-mentioned legs. To oppose tipping, suitable means are provided for preventing pivotal movement of the unified leg assembly after the table has been set in place.

For illustrative purposes, and without limiting the invention thereto, a table according to a preferred embodiment of this invention is illustrated in the accompanying drawing in which:

FIGURE 1 is a bottom plan view of the table, the table being rectangular in shape.

FIG. 2 is a vertical, sectional view, substantially on the irregular line 22 of FIG. 1.

FIG. 3 is an enlarged, horizontal, sectional view of the stabilizing side of the table, substantially on the line 3-3 of FIG. 2.

The illustrated table comprises a rectangular top 10,

3,2043% Patented Sept. 7, 1965 a rectangular skirt 12 suitably fixed rigidly to the table top and extending marginally around the under side thereof, rigid legs 14 and 16 at one side of the table and, at the opposite side of the table, a stabilizing leg assembly 18. This leg assembly has, as its principal components, two legs 20 and 22, rigidly interconnected at their upper ends by a crossbar 24 at the center of which the assembly 18 is pivotally connected by a bolt 26, washer 28, and nut to the center of a side piece 12a of the skirt.

The four legs 14, 16, 20, and 22, thus, are in rectangular arrangement close to the outer edges of the table top, and the leg assembly 18 with its legs 20 and 22 is pivotable in a vertical plane parallel to a vertical plane extending through both legs 14 and 16. The table, as thus far detailed, has four legs, but the table top is supported, only triangularly, at the two legs 14 and 16, and at the bolt 26. In that condition, all four legs rest on a fioor surface even though that surface is uneven. Such a table would be useful for some purposes but the tabe top would still be subject to tilting if much weight were placed on any marginal area thereof outside of its triangular support and toward the end where the leg assembly 18 is located.

This invention, however, includes not only the described pivotal leg assembly which achieves table stability, where weight on the table is concentrated toward the center thereof, but also includes means for holding the table against the mentioned tilting by holding said pivotal assembly in any pivoted position which it may assume when all four table legs are in engagement with a floor surface, either even or uneven.

The means for holding the leg assembly 18 in any stabilizing position comprise a pair of downwardly tapering wedge-shaped blocks 32 suitably fixed, as by glue and/or screws (not shown), directly oppositely to each other, upon the inner surfaces of sides 12b and 12c of the skirt, close to the upper ends of the legs 20 and 22, and a pair of wedge slide-bars 34, held upon crossbar 24 in a close sliding fit within straps 36 which limit the wedge bars to sliding movement longitudinally of the crossbar.

The bolt 26 has a shallow-domed head 38, a main shank portion 40, a reduced, threaded end portion 42,

' and an annular shoulder 44 adjoining the two latter portions. With the head 38 of the bolt at the outside of the part 12a of the tables skirt, and the main shank portion of the bolt extending tightly through said skirt part (FIG. 3), the shank portion 40 extends further inwardly with an accurate free-sliding fit within a vertically extending slot 46 in a preferably enlarged central portion 48 of the crossbar 24, and thence, further inwardly between integral inner wedging portions 50 of the wedge slide-bars 34.

The shank 40 is of such length relatively to the parts through which it extends that, when the nut 30 is tightened upon the washer 28 which seats upon the shoulder 44, the parts of and related to the leg assembly are held closely together but are free to function as hereinafter described.

It may be seen from FIG. 2 that the wedge slidebars 34 also have integral outer wedging portions 52 with wedging surfaces 53 abutting wedging surfaces 54 of the blocks 32. Although not essential, the surfaces 53 may be at least slightly convex or may be rounded at their edges to avoid presenting any sharp edge to the surface 54. The over-all lengths of the two slide-bars 34 are such that when their outer ends are in engagement with the blocks 32, the opposing faces of the wedging portions 50 at their inner ends define a downwardly convergent wedging space 56 which, at about a central horizontal plane is of the same Width as the diameter of the shank portion 40 of the bolt 26.

Thus, the bolt 26, which imposes the weight of the adjacent end or side of the table upon the leg assembly 18, is so wedged by the wedge slide-bars 34, that the bolt cannot, under any condition, engage the bottom of the slot 46. The weight of the adjacent end or side of the table, therefore, is communicated indirectly from the bolt 26 through the slide-bars 34 to the crossbar 24 and, thence, to the legs 26 and 22.

Before the table is placed down upon a floor, the leg assembly 18 hangs freely upon the bolt 26 with the latter at the top of slot 46 and the wedging portions 52 of the slide-bars 34 either clear of wedge surfaces 54 or in inactive, non-forceful engagement therewith. When the table is put down upon the floor, all four legs touch the floor because of the fact that the legs 20 and 22 can swing with crossbar 24 about the bolt 26. If the floor is perfectly level, the crossbar will be parallel to the table top 10, the crossbar and the legs 20 and 22 being positioned as shown in full lines in FIG. 2. If the floor is uneven, the crossbar 24 with the legs 20 and 22 will tilt to some extent as indicated in broken lines in said figure.

Irrespective of whether the crossbar 24 is tilted or untilted, depending upon the condition of the floor, the bolt 26, urged downwardly in slot 46 by weight of the adjacent part of the table, acts upon'inner wedging portions 50 of the side-bars 34 to push the latter forcibly outwardly to hold the slide-bars outer wedging portions tightly against the wedge surfaces 54 of the blocks 32.

The mentioned tight engagement of the slide-bars 34 with the blocks 32 serves strongly to oppose tilting of the table top relatively to the leg assembly 18. Also, the effect of imposing weight upon the table top at or near leg 20 or leg 22 is strongly opposed by reason of the fact that the direction of cant of the interacting wedging surfaces of the slide-bars 34 and the blocks 32 is such that the mentioned imposition of weight increases the Wedging effect upon said slide-bars and blocks.

If the table is slid on a floor surface to a new location where the floor is uneven, or if stabilization does not automatically occur when the table is first put in place, it is easily stabilized by lifting the end or side at which the leg assembly 18 is disposed after which that end or side is again lowered to the floor, when self-stabilizing of the table occurs in the manner already described.

If, within this invention, the pivotal leg assembly 18 is employed without the disclosed means for holding that assembly against swinging from a stabilized position, the bolt 26 may extend through a round hole provided in the crossbar 24 instead of the slot 46.

It should also be noted that, if desired, means different than those disclosed herein may be employed within this invention for holding the pivotal leg assembly in a stabilized position relatively to the table top; and such different means may either be automatic or such as to require a separate operation for locking or holding the pivotal leg assembly in a stabilized position.

Obviously, the presently described concepts may be utilized in various other ways without departing from this invention as set forth in the following claims.

I claim:

1. A stabilized four legged table comprising a table top, a first pair of spaced legs rigidly fixed to the table top toward one side thereof, a second pair of legs, leg mounting means connecting the legs of said second pair to the opposite side of the table top for opposite movement relatively to the latter in an approximately vertical plane, and leg control means coacting with the table top and with the second pair of legs to oppose material movement of the latter legs relatively to the table top; said table top and said second pair of legs having opposed locking portions, and said leg control means comprising a locking element carried by one of said locking portions and movable relatively to said one portion into holding engagement with the other of said portions, and holding means, effective after the last-mentioned movement, for holding the locking element against material movement relatively to either of said locking portions.

2. A table according to claim 1, said locking member having a wedging surface, and said holding means including a wedging member carried by the table top and exerting a wedging action upon said wedging surface, in response to weight of the table top, to wedge the locking element into its said holding engagement with the other of said locking portions.

3. A stabilized four legged table comprising a table top, a first pair of spaced legs rigidly fixed to the table top toward one side thereof, a second pair of legs toward the opposite side of the table top, a rigid interconnection between the upper ends of the legs of said second pair, a pivotal connection at said interconnection and between said table top and the second pair of legs, permitting pivotal movement of the latter legs relatively to the table top in a common, approximately vertical plane and opposing material movement of the latter legs laterally of said plane, and leg control means coacting with the table top and with the second pair of legs to hold the latter legs in any pivotal relationship to the table top that they may assume when the table is supported with all four of its legs in contact with a supporting floor surface; said pivotal connection comprising a bolt carried by said table top in an approximately horizontal position and extending slidably with a close sliding fit within an approximately vertical slot in said interconnection, and said leg control means comprising a rigidly integral, leg control portion of the table top having an approximately vertically extending first friction surface facing said bolt, and a wedge bar carried by said interconnection for approximately horizontal sliding movement, and being restrained against material angular movement relatively to said interconnection and to the legs of said second pair; said wedge bar having a second friction surface, at its outer end, engageable with said first surface, and a wedging surface at its inner end which, when the two said friction surfaces are interengaged, extends downwardly alongside of and at least partially underneath and in engagement with said bolt when the latter is spaced above the lower end of said slot, whereby a downward movement of the bolt in the slot wedges the wedge bar against said first friction surface to hold the second pair of legs against pivotal movement relatively to the table top.

4. A table according to claim 3, said rigid interconnection comprising a rigid crossbar, rigidly fixed at its opposite ends to the upper ends of the legs of said second pair, said pivotal connection being at the center of said crossbar, the table top being provided with two such leg control portions, the said friction surfaces of which face each other and face said bolt, and two of said wedge bars being provided, slidably carried by said crossbar and being wedgingly slidable outwardly by said bolt, responsively to the weight of the table top, to forcibly engage said leg control portions and thereby hold the latter legs against movement relatively to the table top.

5. A table according to claim 4, said first friction surfaces each extending downwardly and in a direction away from said bolt whereby to cause downward force imposed upon the table top to enhance the restraint against angular movement of the second pair of legs relatively to the table top.

6. A table according to claim 5, said second friction surfaces being approximately parallel to said first friction surfaces in contact therewith.

7. A readily stabilizable four legged table, comprising a table top, an inverted U-shaped leg assembly of two legs and a rigid crossbar rigidly interconnecting them at their upper ends, said crossbar being formed with a vertical, parallel-sided slot, formed centrally therein, a pivot pin fixed to the table top toward one side thereof and extending horizontally into said slot with a sliding fit to constitute a pivotal connection of said leg assembly to the table top, means coacting between said crossbar and said pivot pin limiting material movement of the leg assembly to pivotal movement in a plane extending transversely of said pivot pin, a pair of spaced legs fixed to the table top underneath and toward the opposite side of the latter at points on the table top which, with said pivotal connection, define the corners of a triangular support area of the table top, leg control members on the underside of the table top and rigidly integral with the latter and having opposed upright surfaces facing said pivotal connec tion, and a pair of rigid, wedging slide bars horizontallyslidably carried by said crossbar and substantially held against other than said sliding movement relatively to the crossbar; the outer ends of said slide bars being engageable with said opposed surfaces, and the inner ends of said slide bars being wedgingly engageable by said pivot pin in downward movement of the latter within said slot whereby to urge the slide bars outwardly and forcibly against said opposed surfaces to oppose angular movement of the leg assembly relatively to the table top and 6 thereby oppose tilting of the table top from the effect of force imposed downwardly upon the latter, outside of said triangular support area.

8. A table according to claim 7, said opposed surfaces of said leg control members extending upwardly toward each other whereby to enhance said opposition to angular movement of the leg assembly relatively to the table top.

References Cited by the Examiner UNITED STATES PATENTS 467,811 1/92 Humphreys 248l88.3

FOREIGN PATENTS 390,598 4/ 33 Great Britain.

903,63 6 8 62 Great Britain.

CLAUDE R. LE ROY, Primary Examiner. 

1. A STABILIZED FOUR LEGGED TABLE COMPRISING A TABLE TOP, A FIRST PAIR OF SPACED LEGS RIGIDLY FIXED TO THE TABLE TOP TOWARD ONE SIDE THEREOF, A SECOND PAIR OF LEGS, LEG MOUNTING MEANS CONNECTING THE LEGS OF SAID SECOND PAIR OF THE OPPOSITE SIDE OF THE TABLE TOP FOR OPPOSITE MOVEMENT RELATIVELY TO THE LATTER IN AN APPROXIMATELY VERTICAL PLANE, AND LEG CONTROL MEANS COACTING WITH THE TABLE TOP AND WITH THE SECOND PAIR OF LEGS TO OPPOSE MATERIAL MOVEMENT OF THE LATTER LEG RELATIVELY TO THE TABLE TOP; SAID TABLE TOP AND SAID SECOND PAIR OF LEGS HAVING OPPOSED LOCKING PORTIONS, AND SAID LEG CONTROL MEANS COMPRISING A LOCKING ELEMENT CARRIED BY ONE OF SAID LOCKING PORTIONS AND MOVABLE RELATIVELY TO SAID ONE PORTION INTO HOLDING ENGAGEMENT WITH THE OTHER OF SAID PORTIONS, AND HOLDING MEANS, EFFECTIVE AFTER THE LAST-MENTIONED MOVEMENT, FOR HOLDING THE LOCKING ELEMENT AGAINST MATERIAL MOVEMENT RELATIVELY TO EITHER OF SAID LOCKING PORTIONS. 